Tuesday, February 21, 2012

February 21, 2012

Today, we turned in our Hydra/Planaria lab (and also reviewed the answers to the questions), and we got back pages 15-18 and 11-14, and the Lab #44.

We also completed pages 7-10 in our note packet, all about the protist kingdom--extra info can be found in Chapter 15, pages 311-316 in our textbook. To sum up all the information, with key points as written in our packet:

Protists are the first eukaryotes to evolve from prokaryote (bacteria) ancestors; they are much more complex than prokaryotes.

How did eukaryote cells, as well as their membrane-enclosed organelles, evolve?

2 theories of these processes:

All organelles (except mitochondria and chloroplasts) evolved from inward folds of the plasma membrane of a prokaryotic cell.

Endosymbiosis: Largely developed by Lynn Margulis of the University of Massachusetts:

"Chloroplasts and Mitochondria evolved from small prokaryotes that established residence in other, larger host prokaryotes."

Mitochondria evolved 1st

Protists vary in structure and function more than any other group or organism

MOST are unicellular, but some are colonial or multicellular.

The four major categories are:

Protozoans: They ingest food and thrive in all types of aquatic environments, including wet soil and the watery environment inside animals (parasites).

Slime Molds: Resemble fungi in appearance and lifestyle, but are NOT closely related at all... Role=decomposers

Next, we filled out unit packet page 33, "Examining a Phylogenetic Tree", as a class. Lastly, we did a lab on page 35 in our unit packets, in which we classified real organisms (around the classroom--from centipedes to scorpions) based on their appearances into the correct phylum.

The homework for tonight is:

To finish the "General Classification of Invertebrates" lab (pages 35-38)

Prep for labs on pages 45-54

The "Nature" assignment (due 3/2)

And to read CH 17 if you haven't already!!!

(It also might be a good idea to read up on pill bugs, just to get a little background knowledge for an upcoming lab)